Suppose you mean 3x/(5 + x) = 2/3. We have:
3x / (5 + x) = 2 / 3
(3x)(3) = (2)(5 + x)
9x = 10 + 2x
9x - 2x = 10
7x = 10
x = 10 / 7
Suppose you mean (3x / 5) + x = 2/3. We have:
(3x / 5) + x = 2 / 3
(8x / 5) = 2 / 3
(8x)(3) = (5)(2)
24x = 10
x = 10 / 24
x = 5 / 12